Must be the water.
I've been to Amsterdam-a few times. I swear all the native
Dutch woman are pretty tall.
Here is some stats from Wikepeda:
The people of the Netherlands are amongst the tallest in the world, with an average height of about 1.85 m (6 ft 0.8 in) for adult males and 1.68 m (5 ft 6 in) for adult females.